Wearing out a diamond stone?

[SpookyPistolero]

In my seemingly eternal quest to put an edge on one of my un-sharpenable knives, I've worn out my first sharpening stone. It's just one of the 'E-Z Lap Diamond Pocket Stones', but I've had it for a long time and used it on lots of knives, without this happening. After trying to get this blade sharp, I've literally worn out the middle section of the stone. It's almost perfectly smooth now, whereas before it was as rough as when I first got it.

After having had this one for so long, I mostly assumed these stones lasted just about forever. Has anyone else worn this type of stone out? Just curious...

PS- I really hate not being able to make this knife sharp... :grumpy:

 

[Dr. Nick]

I didn't think that the diamond stones wore out. When you use them though, the diamond particles fracture and become smaller making the surface seem smoother. Clean up the surface (rinse it in water and maybe scrub it with a Scotchbrite pad) and see if it doesn't start cutting again.

Rob

 

[Kohai999]

I didn't think that the diamond stones wore out. When you use them though, the diamond particles fracture and become smaller making the surface seem smoother. Clean up the surface (rinse it in water and maybe scrub it with a Scotchbrite pad) and see if it doesn't start cutting again.

Rob

Rob, that is not really what happens.

The substrate on diamond stones is steel. The industrial diamonds or CBN is bonded to the substrate with nickel. What is actually happening is that the diamonds are tearing out of this bonding matrix with time. In other words, the diamonds are coming out of the stone. The stone will still cut, but not as aggressively. Eventually all you are left with is nickel coated steel.

Best Regards,

STeven Garsson

 

[1whitefoot]

They do wear out.
I have a few laying around here.
When they get real smooth I use them for like a final polish on the edge.
New ones are a little too aggressive.
I really like the size tho' :thumbup:

 

[SpookyPistolero]

Good to know. Still sad to have lost a stone I've had for so long!

I actually did clean it up, but it's as smooth as the back side now. I think I'll have to break down and buy a Lansky kit..

 

[hardheart]

I've read of the polycrystalline Eze laps breaking down, plus there can be pullout if you are sharpening softer steel, so you could have diamonds both coming apart and coming out.

 

[pablo486]

I've read in other threads here that the polycrystalline stones are also more susceptible to getting "torn" off if you sharpen with too much pressure.

Also, if you can sharpen freehand, you might want to pick up a some kind of bench stone instead of the Lansky kit. All other differences aside, the stones on the Lansky kits are pretty small so it's slower then a big ole bench stone.